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BC-348 receiver help.
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January 28th 04, 12:55 AM
N2EY
Posts: n/a
In article ,
r (Mike Knudsen) writes:
The B- must be fed thru a filter choke, whose toehr end delivers it to
ground. The negative back bias developed across the choke is used to bias
the
audio output tube's grid negative. Its cathode is straight grounded, so if
you
run without this choke and B-, the output will draw excessive current and
distort.
That choke is in the same sealed case as the output transformer.
Exactly. The wires that come to the dynamotor include "B-" which is not
grounded. Hook it up as described and the choke will be in circuit.
A question for the poster I'm responding to: Is that 220 VDC max including
the choke, or just from B+ to chassis ground? I'm assuming the whole thing
(choke included).
It's what you see from B+ to B- at the output of the supply. There's a whole
description in the manual. The idea was to compensate for dynamotor output
variations.
73 de Jim, N2EY
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